Exchange Mail Issue

I'm pretty sure that my old HTC did this but my new Samsung isn't doing it. I have a work exchange account on my phone that is syncing new mail fine but if I open and read a new message on say my PC it isn't dropping off the new messages on my phone. Another words the mail icon is still present. Am I missing a setting?

That's how it's always been with my Samsung phones (Galaxy S2, Note 2, S4, Note 3, Note 10.1), so I guess it's got to do with E-Mail app from Sammy... didn't know that in HTC's when you read it in your PC it would clear the read count in your phone, too